The leaves of as many as 15 Epimedium species are used to make yin yang huo, an herb in traditional Chinese medicine. The name literally means "obscene goat leaves of pulse plants," which is translated as "horny goat weed" in English. Epimedium species that are used to make horny goat weed grow in China and Korea. The leaf of the plant is most commonly used as medicine, although other parts may sometimes be used.

Horny goat weed is rarely used as a single ingredient. It is traditionally used as an ingredient in a tonic to help promote health.

There is a lack of well-designed studies to support the use of horny goat weed. The herb has been studied for possible benefits in clogged arteries, menopause, and sexual disorders. More research is needed to determine its safety and effectiveness.

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

GRADE *

Early studies suggest that horny goat weed extracts may help improve bone density. Although the results are promising, more research is needed before conclusions can be made.

C

Horny goat weed is traditionally used to treat heart disease. Some research has suggested that the herb may improve symptoms of blood vessel diseases. More studies are needed before firm conclusions can be made.

C

Some research has suggested that a combination of horny goat weed and Chinese yam may improve symptoms and quality of life in people who have chronic obstructive pulmonary disease (COPD). Although this is promising, more research is needed in this area.

C

Some research has suggested that horny goat weed extract may benefit sex hormone and lipid levels in postmenopausal women. More research is needed before firm conclusions can be made in this area.

C

Early research suggests that a horny goat weed mixture with or without alprostadil may improve symptoms of diabetic kidney disease. Although this is promising, more research is needed before firm conclusions can be made.

C

Early research suggests that a combination product containing horny goat weed may help treat polycystic ovarian syndrome. More research is needed in this area.

C

Horny goat weed is traditionally used to increase fertility. Early research suggests that the herb may improve sexual performance and quality of life in people being treated for kidney failure. However, more research is needed before conclusions can be made.

C

* Key to grades

A: Strong scientific evidence for this useB: Good scientific evidence for this useC: Unclear scientific evidence for this useD: Fair scientific evidence for this use (it may not work)F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

In general, various traditional doses have been used. These include 6-15 grams of horny goat weed daily, a decoction (made from five grams of horny goat weed simmered in 250 milliliters of water for 10-15 minutes) three times daily, horny goat weed granules, powdered horny goat weed herb in capsules, or five milliliters of 20% tincture three times daily before meals.

To treat chest pain, four to six 0.3-gram tablets (equivalent to 2.7 grams of raw material in each tablet) have been taken by mouth twice daily for one month, stopped for 7-10 days, then continued in a second series.

To treat chronic bronchitis, four to six 0.3-gram tablets (equivalent to 2.7 grams of raw material in each tablet) have been taken by mouth twice daily for one month, stopped for 7-10 days, then continued in a second series.

To treat hormonal effects in postmenopausal women, 300 milliliters of horny goat weed extract has been taken by mouth daily for six months.

To treat nerve disorders, four to six 0.3-gram tablets (equivalent to 2.7 grams of raw material in each tablet) have been taken by mouth twice daily for one month, stopped for 7-10 days, then continued in a second series.

Doses of two milliliters of horny goat weed (equivalent to one gram of raw material) have been injected into the muscle.

Children (under 18 years old)

There is no proven safe or effective dose for horny goat weed in children.

Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Avoid if allergic or sensitive to horny goat weed (Epimedium grandiflorum), its parts, or related plants in the Berberidaceae family.

Side Effects and Warnings

In general, horny goat weed is well tolerated. Side effects related to the stomach appear to be most common.

Horny goat weed is possibly safe when taken by mouth at commonly used dosages (about five grams daily). It is possibly safe when taken by mouth as 300 milliliters of horny goat weed extract daily for up to six months.

Use cautiously in people who have heart disease. Horny goat weed may cause changes in heart rhythm.

Horny goat weed may cause low blood pressure. Caution is advised in people with blood pressure disorders or in those taking drugs, herbs, or supplements that lower blood pressure.

Use cautiously in people who have musculoskeletal disorders. Horny goat weed may worsen symptoms.

Use cautiously in people who have mental illnesses, such as bipolar disorder. Horny goat weed may cause aggression or irritability.

Use cautiously in people who have immune disorders. Horny goat weed may affect the immune system or worsen symptoms.

Horny goat weed may increase the risk of bleeding. It may cause nosebleed. Caution is advised in people with bleeding disorders or those taking drugs that may increase the risk of bleeding. Dosing adjustments may be necessary.

Use cautiously in people who are taking monoamine oxidase inhibitors (MAOIs).

Use cautiously in people who have homocysteine disorders.

Use cautiously in people who have thyroid disorders. Horny goat weed may affect thyroid activity.

Use cautiously in people who have respiratory disorders. Horny goat weed may cause breathing difficulty when taken in large doses.

Use cautiously in people who have dizziness. Horny goat weed may cause dizziness.

Use cautiously in children and in pregnant or breastfeeding women, due to a lack of safety information.

Avoid in people who have hormonal disorders or those taking birth control. Horny goat weed may affect hormone levels.

Avoid in people who have yin deficiency, based on Chinese philosophy.

Avoid if allergic or sensitive to horny goat weed (Epimedium grandiflorum), its parts, or related plants in the Berberidaceae family.

Pregnancy and Breastfeeding

There is a lack of scientific evidence on the use of horny goat weed during pregnancy or breastfeeding.

Horny goat weed may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (blood thinners) such as warfarin (Coumadin®) or heparin, antiplatelet drugs such as clopidogrel (Plavix®), and nonsteroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).

Horny goat weed may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.

The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.